Braum seats are yet to be installed. But I do hear good things about them from e93 owners. One owner even said he would never go back to stock M3 seats again.
N54 Cooling - Temp Control Logic and what are your temps during extended track use?
- Thread starter barry@3DM
- Start date
Braum seats are yet to be installed. But I do hear good things about them from e93 owners. One owner even said he would never go back to stock M3 seats again.
Oh yea...I got those already. I got the 313 model 18" wheels at 21lbs. per front wheel. Previous I had the big ass 5 spoke that weighed 34lbs each... shit! I shed probably 40 lbs of wheel weight which is multiplied x10 as regular weight so basically, 400 lbs. off the car.
Seats will take another 90 lbs off.
Following the initial conclusions presented in this thread, I decided to jump ahead and add an extra coolant radiator. See detailed post in my build thread here. I should be able to do some logging during January, although not at +100F amb temps unfortunately 
When ordering the radiator, I had to decide whether I wanted to leave enough space for my 7.5 HD race FMIC to be re-installed in the future. My calculations showed that in order to exceed the cooler area x depth of the S54, I would have to use all the space available above my current 7in FMIC. This means, if I keep the radiator in this position, I won't be able to fit a 7.5 FMIC. As I am only running 18-20psi, this should be fine, but others may want to consider placement elsewhere.
When ordering the radiator, I had to decide whether I wanted to leave enough space for my 7.5 HD race FMIC to be re-installed in the future. My calculations showed that in order to exceed the cooler area x depth of the S54, I would have to use all the space available above my current 7in FMIC. This means, if I keep the radiator in this position, I won't be able to fit a 7.5 FMIC. As I am only running 18-20psi, this should be fine, but others may want to consider placement elsewhere.
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Just a quick heads up. I won't be able to test the new coolers this month due to dealing with other issues (boost and oil leaks). So I won't be able to present track log results until end of February unfortunately.
I finally went to the track today to test the new coolers. It was 19C indicated outside, so not exactly hot. Unfortunately the session ended after only 6 minutes / 3 laps, due to a huge accident on track. A VW golf behind me ran out of braking, saw air time and ended up-side down. Fortunately the driver was alright.
I edited the csv file to include both C and F temps and uploaded to datazap:
https://datazap.me/u/asbjoern/gic-temperature-logging?log=1&data=5-14-22
Looking forward to get a full session 20min log next time
Grrr... drove to Guangdong International Circuit with the purpose of finally logging a full session with the new coolers. Weather was dry, 75F... forecast said overcast, and there was no rain nearby according to the weather radar.
I set out. 2 hours later, very close to the track... drip drip drip... whooossh
I will stay here for the night and see if it gets better tomorrow, but chances are very slim.
I set out. 2 hours later, very close to the track... drip drip drip... whooossh
I will stay here for the night and see if it gets better tomorrow, but chances are very slim.
So after a whole evening and night of rain, I woke up to sunshine today. I went to the track around noon, and was the first person to enter the track. There was still a bit of standing water on a few curbs bu otherwise a great day to test.
Conditions today
27C/80F indicated in cluster on track;
21C/70F indicated by weather app. Rh 60%
Some info on the track here. It has two straights long enough to reach 200km/h / 120mph or more if you really push it.
Car setup
DSC = off;
MHD stock cooling;
AC = off, heater/blower = off;
Semi-dry oil sump system = on;
DCT oil cooler = on;
Roof = up;
Mods on car relevant to this test;
Around 380whp, GC lites 2.0;
VRSF-style non-HD 7in FMIC;
CSF AT radiator;
Additional custom radiator, 31row, single pass, 620 x 341mm (outer dimensions, incl end tanks), placed in front of AC condenser;
OEM oil thermostat
OEM oil cooler replaced with 15row, single pass, 290 x 210 x 50mm unit. Stock location.
Semi-dry oil sump oil cooler on drivers side (approx same size as OEM oil cooler)
DCT oil cooler placed in front of additional radiator. (So a total of 4 coolers are placed above the FMIC: 1 DCT - 2 Radiator - 3 Condenser - 4 CSF Radiator)
Stock non-M sport Z4 bumber, no mods;
Stock air intake, snorkel removed.
Results
First I did 8mins of warm up, going faster and faster.
Then I did one cool down lap (not logged)
Then 4 hot laps, pushing 80% (consistently braking 100m earlier than normal at the two main braking zones of the track), and one cool down lap:
The logs include both F and C temps. I stopped pushing after the 4th lap, as I was noticing my coolant had reached an equilibrium, never exceeding 106C / 223F.
Conclusions
Now if I compare to this "one hot lap" log, which was done at another track, in 37C / 100F weather:
It is clear that:
Conditions today
27C/80F indicated in cluster on track;
21C/70F indicated by weather app. Rh 60%
Some info on the track here. It has two straights long enough to reach 200km/h / 120mph or more if you really push it.
Car setup
DSC = off;
MHD stock cooling;
AC = off, heater/blower = off;
Semi-dry oil sump system = on;
DCT oil cooler = on;
Roof = up;
Mods on car relevant to this test;
Around 380whp, GC lites 2.0;
VRSF-style non-HD 7in FMIC;
CSF AT radiator;
Additional custom radiator, 31row, single pass, 620 x 341mm (outer dimensions, incl end tanks), placed in front of AC condenser;
OEM oil thermostat
OEM oil cooler replaced with 15row, single pass, 290 x 210 x 50mm unit. Stock location.
Semi-dry oil sump oil cooler on drivers side (approx same size as OEM oil cooler)
DCT oil cooler placed in front of additional radiator. (So a total of 4 coolers are placed above the FMIC: 1 DCT - 2 Radiator - 3 Condenser - 4 CSF Radiator)
Stock non-M sport Z4 bumber, no mods;
Stock air intake, snorkel removed.
Results
First I did 8mins of warm up, going faster and faster.
Then I did one cool down lap (not logged)
Then 4 hot laps, pushing 80% (consistently braking 100m earlier than normal at the two main braking zones of the track), and one cool down lap:
The logs include both F and C temps. I stopped pushing after the 4th lap, as I was noticing my coolant had reached an equilibrium, never exceeding 106C / 223F.
Conclusions
Now if I compare to this "one hot lap" log, which was done at another track, in 37C / 100F weather:
It is clear that:
- The iat is more or less just following the ambient temp. This makes sense, because it is operating close to ambient temp, and I didn't change power or FMIC. With the 7.5 race FMIC, I think I had 10C lower peak iat, so nothing major.
- It is also clear that peak coolant is lower (107C after many laps vs 118C before after one lap), but it is unknown how much is due to ambient temp and how much is due to the additional radiator. The decrease is somewhat similar to the decrease in ambient temp.
- Transmission temp is a bit lower than coolant, and was also lowered by the same amount as ambient, and I didn't change anything there.
- Engine oil temp is also doing better, but again similar to the decrease in ambient, although the factory location cooler was doubled in size since the 100F log.
So after a whole evening and night of rain, I woke up to sunshine today. I went to the track around noon, and was the first person to enter the track. There was still a bit of standing water on a few curbs bu otherwise a great day to test.
View attachment 24370
Conditions today
27C/80F indicated in cluster on track;
21C/70F indicated by weather app. Rh 60%
Some info on the track here. It has two straights long enough to reach 200km/h / 120mph or more if you really push it.
Car setup
DSC = off;
MHD stock cooling;
AC = off, heater/blower = off;
Semi-dry oil sump system = on;
DCT oil cooler = on;
Roof = up;
Mods on car relevant to this test;
Around 380whp, GC lites 2.0;
VRSF-style non-HD 7in FMIC;
CSF AT radiator;
Additional custom radiator, 31row, single pass, 620 x 341mm (outer dimensions, incl end tanks), placed in front of AC condenser;
OEM oil thermostat
OEM oil cooler replaced with 15row, single pass, 290 x 210 x 50mm unit. Stock location.
Semi-dry oil sump oil cooler on drivers side (approx same size as OEM oil cooler)
DCT oil cooler placed in front of additional radiator. (So a total of 4 coolers are placed above the FMIC: 1 DCT - 2 Radiator - 3 Condenser - 4 CSF Radiator)
Stock non-M sport Z4 bumber, no mods;
Stock air intake, snorkel removed.
Results
First I did 8mins of warm up, going faster and faster.
Then I did one cool down lap (not logged)
Then 4 hot laps, pushing 80% (consistently braking 100m earlier than normal at the two main braking zones of the track), and one cool down lap:
The logs include both F and C temps. I stopped pushing after the 4th lap, as I was noticing my coolant had reached an equilibrium, never exceeding 106C / 223F.
Conclusions
Now if I compare to this "one hot lap" log, which was done at another track, in 37C / 100F weather:
It is clear that:
So while I am happy I wasn't able to push any temperatures even close to power reduction today, I am still concerned what will happen in 100F weather. I had really hoped coolant would stay below 100C / 210F as demanded by the DME with the additional radiator, but it does sit in front of the other. I am not sure if I should be concerned with 106C / 223F peak coolant on track but let me know your thoughts.
- The iat is more or less just following the ambient temp. This makes sense, because it is operating close to ambient temp, and I didn't change power or FMIC. With the 7.5 race FMIC, I think I had 10C lower peak iat, so nothing major.
- It is also clear that peak coolant is lower (107C after many laps vs 118C before after one lap), but it is unknown how much is due to ambient temp and how much is due to the additional radiator. The decrease is somewhat similar to the decrease in ambient temp.
- Transmission temp is a bit lower than coolant, and was also lowered by the same amount as ambient, and I didn't change anything there.
- Engine oil temp is also doing better, but again similar to the decrease in ambient, although the factory location cooler was doubled in size since the 100F log.
The extreme short is...
Historically, the coolant target for a BMW engine is no more that 200F for track use (M20, S14, M50, S50, M54, S54, list goes on). Above that they won't last very long. The long 6 cylinder heads (with the exception of the s14) like to warp and blow head gaskets at those temps on the track.
BMW says N54 Volumetric efficiency is 194F. My goal is no more than 200F.
It more likely was managed to target and was able to maintain it. The DME will control temps to 108C (ECO) and 104C (normal) unless changed. You won't get high or high+KFT modes/targets until ambient is 90 or 100F respectively (stock), so your sessions would have been targeted to 104-108C and they are right on that.So after a whole evening and night of rain, I woke up to sunshine today. I went to the track around noon, and was the first person to enter the track. There was still a bit of standing water on a few curbs bu otherwise a great day to test.
View attachment 24370
Conditions today
27C/80F indicated in cluster on track;
21C/70F indicated by weather app. Rh 60%
Some info on the track here. It has two straights long enough to reach 200km/h / 120mph or more if you really push it.
Car setup
DSC = off;
MHD stock cooling;
AC = off, heater/blower = off;
Semi-dry oil sump system = on;
DCT oil cooler = on;
Roof = up;
Mods on car relevant to this test;
Around 380whp, GC lites 2.0;
VRSF-style non-HD 7in FMIC;
CSF AT radiator;
Additional custom radiator, 31row, single pass, 620 x 341mm (outer dimensions, incl end tanks), placed in front of AC condenser;
OEM oil thermostat
OEM oil cooler replaced with 15row, single pass, 290 x 210 x 50mm unit. Stock location.
Semi-dry oil sump oil cooler on drivers side (approx same size as OEM oil cooler)
DCT oil cooler placed in front of additional radiator. (So a total of 4 coolers are placed above the FMIC: 1 DCT - 2 Radiator - 3 Condenser - 4 CSF Radiator)
Stock non-M sport Z4 bumber, no mods;
Stock air intake, snorkel removed.
Results
First I did 8mins of warm up, going faster and faster.
Then I did one cool down lap (not logged)
Then 4 hot laps, pushing 80% (consistently braking 100m earlier than normal at the two main braking zones of the track), and one cool down lap:
The logs include both F and C temps. I stopped pushing after the 4th lap, as I was noticing my coolant had reached an equilibrium, never exceeding 106C / 223F.
Conclusions
Now if I compare to this "one hot lap" log, which was done at another track, in 37C / 100F weather:
It is clear that:
So while I am happy I wasn't able to push any temperatures even close to power reduction today, I am still concerned what will happen in 100F weather. I had really hoped coolant would stay below 100C / 210F as demanded by the DME with the additional radiator, but it does sit in front of the other. I am not sure if I should be concerned with 106C / 223F peak coolant on track but let me know your thoughts.
- The iat is more or less just following the ambient temp. This makes sense, because it is operating close to ambient temp, and I didn't change power or FMIC. With the 7.5 race FMIC, I think I had 10C lower peak iat, so nothing major.
- It is also clear that peak coolant is lower (107C after many laps vs 118C before after one lap), but it is unknown how much is due to ambient temp and how much is due to the additional radiator. The decrease is somewhat similar to the decrease in ambient temp.
- Transmission temp is a bit lower than coolant, and was also lowered by the same amount as ambient, and I didn't change anything there.
- Engine oil temp is also doing better, but again similar to the decrease in ambient, although the factory location cooler was doubled in size since the 100F log.
You should try reflashing your tune at least with MHD race cooling option selected before running next time. It will move all mode targets to 80-85C, except ECO. That will be a 20-28C target drop for the most part and then see how much lower actuals go when actively managed to cooler head temps. Ideally, ECO would be set to 80-85C as well, which is easy enough to do, but is not part of the MHD cooling pre-defined options.
You're not going to get a lot lower temps on stock cooling logics unless it's 100F outside. This is just driving around, but struggled to get oil to 180F on almost 80F day. Stock 335is hardware, no A/C (fan). FYI, fan shows ~7% when it's off, conversion factor is off. Temps are in C:
https://datazap.me/u/rsl/cooling-test-70c-target?log=0&data=3-4-5-7-8-9-11
Either way, MHD cooling is easy to add (select option and reflash current map with it) and would be noticeably better than stock if your coolers can keep up. My car has roughly 2:1 ratio on ECT drop to oil temp drop. Reduce max ECT 30-40F from stock targets, oil max temp drops about 15-20F. If it's cooler out, the ratio is less and max oil temp drops more per ECT. Not sure how it would be on track or with your rads, but just a ballpark on what to expect from oil by dropping ECT.
You can see in the second log that coolant is at 90C before and after the hot laps. This indicates that dme has entered sport mode, probably due to pushing it during warm up and during the hot lapping.
We are modifying the cooler setup this week and I will try and include testing with and without race mode activated next time. May even turn the heater on lol.
I think it has actually been confirmed that the water pump will indeed run at full tilt in ALL cooling modes. So no, the car should not see rising coolant temps of 220f+ if it's running in normal mode targeting 205f.
The big difference the MHD cooling changes make is that you can force the car to run in "High+KFT" mode at all times (by lowering the ambient thresholds) which means that it will drop the coolant temp more aggressively in areas of the race track where coolant temps can be kept low. This then gives you more "headroom" again before temps rise again in the faster parts of the track that require a lot of throttle. so instead of entering the straight away with 205f coolant and peaking 230f you might enter the straight away at 180f coolant and peak 210f.
It works a little bit, but cooling capacity is still exceeded and coolant temps still trend upwards after successive laps.
Haven't been able to keep up with what's being discussed here, too much going on! Would be happy to revisit down the road though.
I shouldn't look at stuff at 2am, I missed the ends. I don't think it can be high or high+KFT, but oil temps, tranny, etc. can request additional cooling and maybe its hitting another mode besides those. There are 10 including fill/bleed, warm up, component protection, emergency, etc. I'm not sure if the outside requests have their own add tables like the heat balance table, change actual target in the same mode or trigger another mode like protection/emergency (80C).
Oil drops at a much slower rate vs. ECT than mine on the road, but that's probably expected.
How did you get that second radiator to fit? From the description it sounds like its sitting above the FMIC, thus you didn't push the stock radiator back at all?
